#include<stdio.h>
# define PI 3.14156;
int main()
{
	double r,c,s;
	printf("please enter the r:");
	scanf("%lf",&r);
	c=2*PI*r;
	s=PI*r*r;
	printf("r=%lf,c=%lf,s=%lf",r,c,s);
	return 0;
}
